/**
 * @file
 * Ethernet Interface Skeleton
 *
 */

/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 *
 * Author: Adam Dunkels <adam@sics.se>
 *
 */

/*
 * This file is a skeleton for developing Ethernet network interface
 * drivers for lwIP. Add code to the low_level functions and do a
 * search-and-replace for the word "ethernetif" to replace it with
 * something that better describes your network interface.
 */


#undef MOUDLE
#define MOUDLE ETHIF
#include "app_cfg.h"
#include "debug_print.h"
#include "arch/sys_arch.h"
#include "lwip/opt.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/pbuf.h"
#include <lwip/stats.h>
#include <lwip/snmp.h>
#include "netif/etharp.h"
// #include "netif/ppp_oe.h"
#include "dma.h"
#include "wlan_intf.h"
#include "wrapper_os.h"
#include "ethernetif.h"
#if LWIP_IPV6
#include "lwip/ethip6.h"
#endif

/* Define those to better describe your network interface. */
#define IFNAME0 'w'
#define IFNAME1 'n'

/**
 * In this function, the hardware should be initialized.
 * Called from ethernetif_init().
 *
 * @param netif the already initialized lwip network interface structure
 *        for this ethernetif
 */
static void
low_level_init(struct netif *netif)
{
    void *adapter;
    struct ethernetif *ethernetif = netif->state;

    /* set MAC hardware address length */
    netif->hwaddr_len = ETHARP_HWADDR_LEN;

    /* maximum transfer unit */
    netif->mtu = 1500;

    /* device capabilities */
    /* don't set NETIF_FLAG_ETHARP if this device is not an ethernet one */
#if LWIP_IGMP
    netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_IGMP | NETIF_FLAG_LINK_UP;
#else
    netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;
#endif

    /* Do whatever else is needed to initialize interface. */
    adapter = wifi_ops_entry.wifi_open_func(1);
    if (NULL == adapter) {
        DEBUG_ERROR("WiFi open failed.\r\n");
        return;
    }

    wifi_register_ethernetif(ethernetif, adapter, (ethif_input_fn)ethernetif_input);

    MEMCPY(netif->hwaddr, ethernetif->mac_addr, netif->hwaddr_len);
}

/**
 * This function should do the actual transmission of the packet. The packet is
 * contained in the pbuf that is passed to the function. This pbuf
 * might be chained.
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
 * @return ERR_OK if the packet could be sent
 *         an err_t value if the packet couldn't be sent
 *
 * @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
 *       strange results. You might consider waiting for space in the DMA queue
 *       to become availale since the stack doesn't retry to send a packet
 *       dropped because of memory failure (except for the TCP timers).
 */

static err_t
low_level_output(struct netif *netif, struct pbuf *p)
{
    struct ethernetif *ethernetif = netif->state;
    struct pbuf *q;
    uint8_t result;
    uint8_t index = 0;
    err_t err = ERR_OK;
    struct tcpip_packet_info tcpip_packet;
    struct tcpip_packet_info *p_packet = &tcpip_packet;

#if ETH_PAD_SIZE
    pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
#endif

    p_packet->packet_len = 0;
    for (q = p; q != NULL; q = q->next) {
        /* Send the data from the pbuf to the interface, one pbuf at a
           time. The size of the data in each pbuf is kept in the ->len
           variable. */
        p_packet->data_ptr[index] = q->payload;
        p_packet->data_len[index] = q->len;
        p_packet->packet_len += q->len;
        index++;
    }
    p_packet->buf_num = index;


    if (ethernetif && ethernetif->adapter && ethernetif->wifi_output) {
        result = ethernetif->wifi_output(ethernetif->adapter, &tcpip_packet);
        if (result == 1) {
            // DEBUG_ERROR("the xmit packet is dropped: out of memory!");
            err = ERR_MEM;
        } else if (result != 0) {
            // DEBUG_ERROR("xmit packet dropped: wifi link not ready!");
            err = ERR_IF;
        }
    }


#if ETH_PAD_SIZE
    pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
#endif

    LINK_STATS_INC(link.xmit);

    return err;
}

/**
 * Should allocate a pbuf and transfer the bytes of the incoming
 * packet from the interface into the pbuf.
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @return a pbuf filled with the received packet (including MAC header)
 *         NULL on memory error
 */
static struct pbuf *
low_level_input(struct netif *netif, struct tcpip_packet_info *rx_packet)
{
    //  struct ethernetif *ethernetif = netif->state;
    struct pbuf *p, *q;
    uint16_t len;
    uint8_t sbuf_index = 0;
    uint8_t new_src_buf = 1;
    uint16_t sbuf_offset = 0;
    uint16_t sbuf_remaining;
    uint16_t dbuf_remaining;
    uint16_t copy_len;
    uint16_t total_copy_len = 0;
    uint8_t *rx_buf_ptr;
    uint8_t i;
    uint8_t pkt_buf_continuous = 1;


    /* Obtain the size of the packet and put it into the "len" variable. */
    len = rx_packet->packet_len;
    if (len == 0) {
        // DEBUG_INFO("eth rx no data");
        return NULL;
    }

    if (len > ETH_RX_BUF_SIZE) {
        DEBUG_ERROR("eth rx buf size not enough");
    }

#if ETH_PAD_SIZE
    len += ETH_PAD_SIZE; /* allow room for Ethernet padding */
#endif

    /* We allocate a pbuf chain of pbufs from the pool. */
    p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);

    if (p == NULL) {
        sys_ms_sleep(15);
        p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
    }

    if (p != NULL) {
#if ETH_PAD_SIZE
        pbuf_header(p, -ETH_PAD_SIZE);  /* drop the padding word */
#endif

        // co_printf("low_level_input, pbuf ptr: 0x%08x, pbuf len: %d\n", p->payload, p->len);

        for (i = 0; i < rx_packet->buf_num - 1; i++) {
            if (rx_packet->data_ptr[i+1] != rx_packet->data_ptr[i] + rx_packet->data_len[i]) {
                pkt_buf_continuous = 0;
                break;
            }
        }

        /* We iterate over the pbuf chain until we have read the entire
        * packet into the pbuf. */
        for (q = p; q != NULL; q = q->next) {
            /* Read enough bytes to fill this pbuf in the chain. The
            * available data in the pbuf is given by the q->len
            * variable.
            * This does not necessarily have to be a memcpy, you can also preallocate
            * pbufs for a DMA-enabled MAC and after receiving truncate it to the
            * actually received size. In this case, ensure the tot_len member of the
            * pbuf is the sum of the chained pbuf len members.
            */
            if (pkt_buf_continuous) {
                sys_memcpy2(q->payload, (rx_packet->data_ptr[0] + sbuf_offset), q->len);
                sbuf_offset += q->len;
            } else {
                dbuf_remaining = q->len;
                while (sbuf_index < rx_packet->buf_num) {
                    rx_buf_ptr = rx_packet->data_ptr[sbuf_index] + sbuf_offset;
                    if (new_src_buf) {
                        sbuf_remaining = rx_packet->data_len[sbuf_index];
                    }
                    if (sbuf_remaining <= dbuf_remaining) {
                        copy_len = sbuf_remaining;
                        // DEBUG_WARNING("1d %08x, s %08x, l %d\n", (uint32_t)((uint8_t *)q->payload + q->len - dbuf_remaining), (uint32_t)rx_buf_ptr, copy_len);
                        sys_memcpy(((uint8_t *)q->payload + q->len - dbuf_remaining), rx_buf_ptr, copy_len);
                        dbuf_remaining -= copy_len;
                        total_copy_len += copy_len;
                        sbuf_index++;
                        sbuf_offset = 0;
                        new_src_buf = 1;
                    } else {
                        copy_len = dbuf_remaining;
                        // DEBUG_WARNING("2d %08x, s %08x, l %d\n", (uint32_t)((uint8_t *)q->payload + q->len - dbuf_remaining), (uint32_t)rx_buf_ptr, copy_len);
                        sys_memcpy(((uint8_t *)q->payload + q->len - dbuf_remaining), rx_buf_ptr, copy_len);
                        sbuf_remaining -= copy_len;
                        total_copy_len += copy_len;
                        sbuf_offset += copy_len;
                        new_src_buf = 0;
                        break;
                    }
                }
            }
        }

        if (pkt_buf_continuous) {
            DEBUG_ASSERT(sbuf_offset == p->tot_len);
        } else {
            DEBUG_ASSERT(total_copy_len == p->tot_len);
        }

#if ETH_PAD_SIZE
        pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
#endif

        LINK_STATS_INC(link.recv);
    } else {
        // DEBUG_WARNING("pbuf_alloc return NULL");
        LINK_STATS_INC(link.memerr);
        LINK_STATS_INC(link.drop);
        sys_ms_sleep(15);
    }

    return p;
}

/**
 * This function should be called when a packet is ready to be read
 * from the interface. It uses the function low_level_input() that
 * should handle the actual reception of bytes from the network
 * interface. Then the type of the received packet is determined and
 * the appropriate input function is called.
 *
 * @param netif the lwip network interface structure for this ethernetif
 */
void
ethernetif_input(struct ethernetif *eth_if,  struct tcpip_packet_info *rx_packet)
{
    struct netif * netif = eth_if->netif;
    struct eth_hdr *ethhdr;
    struct pbuf *p;

    /* move received packet into a new pbuf */
    p = low_level_input(netif, rx_packet);
    /* no packet could be read, silently ignore this */
    if (p == NULL) return;
    /* points to packet payload, which starts with an Ethernet header */
    ethhdr = p->payload;

    switch (htons(ethhdr->type)) {
    /* IP or ARP packet? */
    case ETHTYPE_IP:
    case ETHTYPE_ARP:
#if LWIP_IPV6
    case ETHTYPE_IPV6:
#endif
#if PPPOE_SUPPORT
    /* PPPoE packet? */
    case ETHTYPE_PPPOEDISC:
    case ETHTYPE_PPPOE:
#endif /* PPPOE_SUPPORT */
    /* full packet send to tcpip_thread to process */
        if (netif->input(p, netif) != ERR_OK) {
            LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
            pbuf_free(p);
            p = NULL;
        }
        break;
    default:
        pbuf_free(p);
        p = NULL;
        break;
    }
}

/**
 * Should be called at the beginning of the program to set up the
 * network interface. It calls the function low_level_init() to do the
 * actual setup of the hardware.
 *
 * This function should be passed as a parameter to netif_add().
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @return ERR_OK if the loopif is initialized
 *         ERR_MEM if private data couldn't be allocated
 *         any other err_t on error
 */
err_t
ethernetif_init(struct netif *netif)
{
    struct ethernetif *ethernetif;

    LWIP_ASSERT("netif != NULL", (netif != NULL));

    ethernetif = mem_malloc(sizeof(struct ethernetif));
    if (ethernetif == NULL) {
        LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_init: out of memory\n"));
        return ERR_MEM;
    }

    ethernetif->netif = netif;

#if LWIP_NETIF_HOSTNAME
    /* Initialize interface hostname */
    netif->hostname = "lwip";
#endif /* LWIP_NETIF_HOSTNAME */

    /*
    * Initialize the snmp variables and counters inside the struct netif.
    * The last argument should be replaced with your link speed, in units
    * of bits per second.
    */
    NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, LINK_SPEED_OF_YOUR_NETIF_IN_BPS);

    netif->state = ethernetif;
    netif->name[0] = IFNAME0;
    netif->name[1] = IFNAME1;
    /* We directly use etharp_output() here to save a function call.
    * You can instead declare your own function an call etharp_output()
    * from it if you have to do some checks before sending (e.g. if link
    * is available...) */
    netif->output = etharp_output;
#if LWIP_IPV6
    netif->output_ip6 = ethip6_output;
#endif
    netif->linkoutput = low_level_output;

    /* initialize the hardware */
    low_level_init(netif);

    return ERR_OK;
}

void ethernetif_register_wifi(void *ethif, void *adapter, uint8_t *mac_addr, wifi_output_fn xmit_func)
{
    struct ethernetif *ethernetif = (struct ethernetif *)ethif;

    ethernetif->adapter = adapter;

    sys_memcpy(ethernetif->mac_addr, mac_addr, NETIF_MAX_HWADDR_LEN);

    ethernetif->wifi_output = (wifi_output_fn)xmit_func;
}

void ethernetif_deinit(struct ethernetif *eth_if)
{
    if (eth_if != NULL) {
        mem_free(eth_if);
    }
}
